02832nas a2200265   4500008004100000022001400041245012000055210006900175260000900244300001400253490000600267520190400273653002502177653001802202653001702220653003102237653003002268653002102298100002102319700002302340700003002363700001702393700002402410856013202434       2021                        eng d  a2574-096200aZinc-air batteries catalyzed using Co3O4 nanorod-supported N-doped entangled graphene for oxygen reduction reaction0 aZincair batteries catalyzed using Co3O4 nanorodsupported Ndoped   cMAY   a4570-45800 v43 a<p>The work reported here deals with the development of an efficient non-platinum electrocatalyst for electrochemical oxygen reduction reaction (ORR) through a sequential pathway involving hydrothermal treatment followed by freeze-drying to build the desired structural architecture of the catalyst. The designed catalyst (Co3O4/nitrogen-doped entangled porous 3D graphene (NEGF)), which contains Co3O4 nanorods anchored on the surface of three-dimensional (3D)-structured N-doped graphene, was found to display higher ORR activity during single-electrode testing and demonstrate a Zn-air battery (ZAB) system. Under the hydrothermal treatment at 180 degrees C, in the presence of ammonia, nitrogen was doped into the carbon framework of graphene, which subsequently formed a self-assembled entangled 3D structure of graphene after freeze-drying. The hydrothermal treatment and freeze-drying processes were found to play vital roles in tuning the morphological and structural features of the catalyst. The doped nitrogen, apart from its favorable contribution toward ORR, helped facilitate efficient dispersion of oxide nanorods on graphene. Co3O4/NEGF displayed remarkable ORR activity in 0.1 M KOH solution, as evident from the 60 mV onset potential shift compared to the state-of-the-art Pt/C catalyst and the Tafel slope value of 74 mV dec(-1) vs 68 mV dec(-1) for Pt/C. The ZAB fabricated by employing Co3O4/NEGF as the cathode catalyst was found to be an efficient competitor for the system based on the Pt/C cathode. This high performance has been credited to the controlled interplay of the governing factors such as the interfacial interactions leading to the efficient dispersion of metal oxide nanorods, increased catalyst surface area, the cooperative effect arising from the defects present in the N-doped porous 3D graphene, and the synergetic interactions operating in the system.</p>10acobalt-oxide nanorod10afreeze-drying10ahydrothermal10aN-doped entangled graphene10aoxygen reduction reaction10azinc-air battery1 aManna, Narugopal1 aSingh, Santosh, K.1 aKharabe, Geeta, Pandurang1 aTorris, Arun1 aKurungot, Sreekumar  uhttps://library.ncl.res.in/content/zinc-air-batteries-catalyzed-using-co3o4-nanorod-supported-n-doped-entangled-graphene-oxygen03376nas a2200337   4500008004100000022001400041245023000055210006900285260000800354490000700362520209900369653000702468653002602475653001402501653002702515653001802542653003002560653003002590653003402620653003402654100003002688700002002718700003302738700001802771700002702789700002002816700001802836700003602854700002402890856012402914       2024                        eng d  a1613-681000aAluminium, nitrogen-dual-doped reduced graphene oxide Co-existing with cobalt-encapsulated graphitic carbon nanotube as an activity modulated electrocatalyst for oxygen electrocatalyst for oxygen electrochemistry applications0 aAluminium nitrogendualdoped reduced graphene oxide Coexisting wi  cAUG0 v203 a<p>
	There is a rising need to create high-performing, affordable electrocatalysts in the new field of oxygen electrochemistry. Here, a cost-effective, activity-modulated electrocatalyst with the capacity to trigger both the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER) in an alkaline environment is presented. The catalyst (Al, Co/N-rGCNT) is made up of aluminium, nitrogen-dual-doped reduced graphene oxide sheets co-existing with cobalt-encapsulated carbon nanotube units. Based on X-ray Absorption Spectroscopy (XAS) studies, it is established that the superior reaction kinetics in Al, Co/N-rGCNT over their bulk counterparts can be attributed to their electronic regulation. The Al, Co/N-rGCNT performs as a versatile bifunctional electrocatalyst for zinc-air battery (ZAB), delivering an open circuit potential approximate to 1.35 V and peak power density of 106.3 mW cm-2, which are comparable to the system based on Pt/C. The Al, Co/N-rGCNT-based system showed a specific capacity of 737 mAh gZn-1 compared to 696 mAh gZn-1 delivered by the system based on Pt/C. The DFT calculations indicate that the adsorption of Co in the presence of Al doping in NGr improves the electronic properties favoring ORR. Thus, the Al, Co/N-rGCNT-based rechargeable ZAB (RZAB) emerges as a highly viable and affordable option for the development of RZAB for practical applications. This manuscript reports the development of a new bifunctional catalyst that exhibits high activity and stability under practical operating conditions. The catalyst (Al, Co/N-rGCNT) is made up of aluminium, nitrogen-dual-doped reduced graphene oxide sheets co-existing with the in situ formed cobalt-encapsulated CNT units is synthesized by a scalable pyrolysis method in an inert Ar atmosphere. The developed electrocatalyst achieved enhanced the oxygen reduction reaction (ORR) and the oxygen evolution reaction OER activity as a result of the favorable synergistic modulations and the system can serve as a process-friendly air-electrode for rechargeable zinc-air battery (RZAB). image</p>
10aAl10aBifunctional catalyst10aDFT study10aencapsulated structure10aN-dual doping10aOxygen Evolution Reaction10aoxygen reduction reaction10arechargeable zinc-air battery10aX-ray absorption spectroscopy1 aKharabe, Geeta, Pandurang1 aBarik, Sidharth1 aVeeranmaril, Sudheesh, Kumar1 aNair, Aathira1 aIllathvalappil, Rajith1 aYoyakki, Athira1 aJoshi, Kavita1 aVinod, Chathakudath, Prabhakara1 aKurungot, Sreekumar  uhttps://library.ncl.res.in/content/aluminium-nitrogen-dual-doped-reduced-graphene-oxide-co-existing-cobalt-encapsulated